Recently, so-called regenerative medicine, taking out a part of human body such as cells and tissues of skin, cartilage, bone, blood vessel, and organs, cultivating outside the body, and using in treatment of a same subject or a different patient is developed and partly put in use.
In such regenerative medicine, cells are cultivated by supplying liquid culture medium containing nutrients into culture container, seeding cells in the liquid culture medium, and cultivating in the incubator in prescribed culture conditions. At this time, culture medium exchanging operation that discharging the spent culture medium and charging fresh culture medium is carried out periodically, and subculture operation are performed. In general, such operation manually operated by workers, but this work takes much time and labor. Besides, a large cost is required for preventing from contamination by workers. Accordingly, it has been considered to develop an apparatus using robots.
As prior art of this kind, an automatic culture medium exchange apparatus is proposed (for example, see Japanese Laid-Open Patent Publication No. 2002-262856 (pages 5-7, FIGS. 1 and 2)), in which culture containers are taken out of multi-stage incubator by an orthogonal conveying robot, dismounted culture containers are conveyed to predetermined position by conveyor, the lids of culture containers are removed by an dedicated lid opening robot, containers are further conveyed to predetermined position by conveyor, and culture medium in culture containers is discharged and supplied by dedicated machine.
The patent document described above also discloses an automatic culture cell exchange method for realizing the operation of controlling robots by computer, inclining the container when exchanging the liquid culture medium, sucking the spent culture medium by pipet, and supplying a fresh culture medium, by an exclusive machine.
However, since the automatic culture medium exchange apparatus of the above patent document is of orthogonal type, a wide working space is needed when taking out culture containers from multi-stage incubator, conveying the culture containers to cultivation operation unit and removing lids, discharging and supplying culture medium, and in addition, the position or direction of gripped object cannot be changed. Moreover, because a series of operations must be done while using many robots in cooperation, complicated control is needed and much time is consumed. Using plural robots, countermeasures for prevention of contamination are also essential.
Meanwhile, in cell cultivation, cells grow by sticking to the bottom of the culture container, and no longer grow when the bottom is full. Accordingly, subculture is needed for dispensing the grown cells into plural culture containers. In this subculture, a small amount of cell exfoliation agent (for example, trypsin) is supplied (added) in the container, and cells sticking to the bottom of culture container are exfoliated. However, this cell exfoliation agent dissolves protein and is hence harmful for cells, and it is desired to use in a small amount and in a short time. For example, in manual operation for exfoliating cells by workers, using a small amount of chemical, the small amount of chemical is distributed to the whole surface by inclining the culture container two-dimensionally, and entire cells are exfoliated.
Because it is difficult for the conventional orthogonal type automated apparatus to realize the operation that a small amount of chemical is distributed widely by inclining the culture container, and similar effects are realized by diluting the chemical (or not diluting) and supplying a slightly larger amount (for example, until the entire cells are immersed in the chemical in horizontal state). However, when a large amount of chemical is used, cells may be destroyed, and such method is not recommended.
On the other hand, in the field of regenerative medicine, to be liberated from shortage of donors or immunological rejection due to use of autologous cells, cell cultivation in various clinical departments or cell cultivation of a large amount may be needed in future.
It is hence an object of the invention to provide an automatic cell cultivation apparatus capable of conveying culture containers, exchanging culture medium, and operating other tasks promptly by using a multijoint robot.